Yichang Testing Technique Research Institute

Yichang, China

Yichang Testing Technique Research Institute

Yichang, China
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Wu X.,Yichang Testing Technique Research Institute | Moog C.H.,CNRS Research Institute of Communication and Cybernetics of Nantes | Marquez-Martinez L.A.,Research Center Cientifica Educacion Superior Of Ensenada | Hu Y.,South China University of Technology
Aerospace Science and Technology | Year: 2013

A new concept of airship without thrust, elevator or rudder is considered in this paper. It is actuated by a moving mass and an internal air bladder with adjustable mass. This results into the motion of the center of gravity and the change of the net lift. The development of this concept of airship is motivated by energy saving. The moving mass and the airships rigid body are viewed independently, which renders the modeling easy and displays clearly the interconnection of the two subsystems. An eight degrees-of-freedom (DOF) complete nonlinear mathematical model of this airship is derived through the Newton-Euler approach. The dynamics in the vertical plane are analyzed and controlled, using maximal feedback linearization. The modeling, analysis, and control are solved for special cases of the airship which become gradually complex. The most constrained case reduces to a two-DOF system. It is shown that the basic properties of this two-DOF mechanical system remain instrumental for the analysis and synthesis of advanced airships. These properties are far from being obvious when the most complex model is considered. © 2012 Elsevier Masson SAS.


Song C.H.,Yichang Testing Technique Research Institute
Applied Mechanics and Materials | Year: 2014

An improved ant colony algorithm based grid environment model for global path planning method for USV was introduced. The main idea of the improved ant colony algorithm was distributing each ant route dynamically. When the active ant was selecting the next route, this algorithm program determined the nearest direction to the end point. There were many possible route points which were distributed artificially. Thereby, the probability for each ant to choose the right direction was increased. The simulating results demonstrate that the improved ant colony algorithm in this paper is very suitable for solving the question of global path planning for USV system in the complex oceanic environment where there are a lot of obstacles. At the same time, this method costs less time, and the path is very smooth. © (2014) Trans Tech Publications, Switzerland.


Song C.H.,Yichang Testing Technique Research Institute
Applied Mechanics and Materials | Year: 2013

This paper drives the asymptotical stability conditions for a class of linear systems with time delay. First, a series of integral inequalities based on quadratic term are formulated by combining Leibniz-Newton formula. Next, based on Lyapunov-Krasovskii functional method and linear matrix inequality, the sufficient conditions of delay-dependent stability are derived to ensure the linear systems with time delay are asymptotically stable. Last, the results are illustrated by some numerical examples and the delay bounds obtained in this paper are of less conservative. © (2013) Trans Tech Publications, Switzerland.


Song C.H.,Yichang Testing Technique Research Institute
Applied Mechanics and Materials | Year: 2013

This paper stadies the problem of the asymptotical stability for a time-delayed systems. By using LMI method, a new approach is used to derive a delay-dependent sufficient condition, which can guarantee that the time-delayed systems with multiple time delays is asymptotical stable. At last, a numberical example is given to show that the new theorem is more effective than the present methods. © (2013) Trans Tech Publications, Switzerland.


Liu Z.X.,Yichang Testing Technique Research Institute | Guan H.,Yichang Testing Technique Research Institute | Zhen W.G.,Huazhong University of Science and Technology
Applied Mechanics and Materials | Year: 2013

Optimum distribution of viscoelastic materials of damped sandwich plate composite for suppressing plate vibration is investigated. A solid isotropic material with penalization model is described based on the proposed interface finite element of viscoelastic layer. The objective function is chosen as maximization of the modal loss factor. Numerical results show that the optimum distributions of viscoelastic materials are mainly at the place where large shear displacements would be happened. © 2013 Trans Tech Publications Ltd, Switzerland.


Liu Z.X.,Yichang Testing Technique Research Institute
Advanced Materials Research | Year: 2011

There are many benchmark problems in computational aeroacoustics (CAA) and acoustic mode in the annular duct with uniform mean flow is a problem of this kind. The energy relation of the duct mode is deduced from the governing equation, Euler equations in this paper. If the sound power level, angular frequency, azimuthal mode number and radial mode number are given, the acoustic mode in the annular duct can be expressed explicitly by the deduced results. The simulation of two different cases shows the propagation of a single acoustic mode in annular duct pictorially. © (2011) Trans Tech Publications.


Zhou Y.-Y.,Yichang Testing Technique Research Institute
Applied Mechanics and Materials | Year: 2011

An example of a central air-conditioning project of a rebuilt department store is described in this paper. The design of air system, water system, layout and operations for the air conditioning system is presented in this paper. The system is different form ordinary ones because the floor height is lower; so many special considerations must be taken during the design. In addition, the low cost and easy maintenance place an important role in the design. The operational result of the design is promising and it can be referenced by other designers. © (2011) Trans Tech Publications.


Qin Y.,Yichang Testing Technique Research Institute | Zhang Y.,Yichang Testing Technique Research Institute
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

An object detection for vision-aided inventory counting is developed. The propose approach is simple to use and reduce the workload remarkably. Meanwhile, the approach count the items of interest almost in real time with an acceptable precision, which is desirable in inventory counting. The experiment results show that the proposed approach is efficient to fulfill the counting task. © 2015 SPIE.


Liu Z.,Yichang Testing Technique Research Institute
Advanced Materials Research | Year: 2012

There are many benchmark problems which have exact solutions or experiment data to gauge the simulation of aeroacoustic problems. Annular duct acoustic modes are good benchmark problems of this kind. The waves propagated along the duct can be considered as the summation of infinite Fourier modes. The energy relations of a single Fourier mode are deduced from governing equations in this paper. To investigate the properties of acoustic wave propagating along the duct, it's necessary to decompose acoustic waves in the duct into multiple Fourier modes; the decomposition methods are presented. © (2012) Trans Tech Publications.


Cao L.,Yichang Testing Technique Research Institute
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

Due to the complex constraints, more uncertain factors and critical real-time demand of path planning for USV(Unmanned Surface Vehicle), an approach of fast path planning based on voronoi diagram and improved Genetic Algorithm is proposed, which makes use of the principle of hierarchical path planning. First the voronoi diagram is utilized to generate the initial paths and then the optimal path is searched by using the improved Genetic Algorithm, which use multiprocessors parallel computing techniques to improve the traditional genetic algorithm. Simulation results verify that the optimal time is greatly reduced and path planning based on voronoi diagram and the improved Genetic Algorithm is more favorable in the real-time operation. © 2015 SPIE.

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